The Tello site in southern Iraq is home to the world's oldest bridge. ( Dani Tagen/British Museum)The world's oldest-known bridge, an ancient Sumerian structure in Iraq, is to be used by the British Museum as a training site to teach two groups of female archaeologists the skills to restore the country's Islamic State-ravaged heritage.

After a conflict that saw Isis jihadists destroy large parts of Iraq's archaeological heritage -- including the historic sites at and Nineveh -- the museum will in April begin a training programme for eight women from the Mosul area, most of whom have been living as refugees.

The training will be split between London and the Tello site in southern Iraq, near the city of Naseriyah and home to one of the world's oldest civil engineering projects, the Sumerian bridge at the entrance to the 4,000-year-old city of Girsu, which is the focus of the project.

Although unaffected by Isis's predations, Girsu -- first discovered in the 19th century -- has been damaged through erosion and neglect.

Significant as the first major Sumerian site to be excavated, in works that continued until the 1930s, Girsu was occupied from the early dynastic period (2900-2335BC) until 200BC, and at its height was a major administrative centre.

Sebastien Rey, the British Museum's lead archaeologist both on the bridge and for the training project, believes experience in restoration and research at the bridge site can be used as a safe pilot for Iraq's Isis-damaged heritage, not least because of the site's topographical similarity in layout to Iraq's other great archaeological sites.

"There is little doubt that this is the world's oldest bridge," he told the Guardian. "It is a huge monument that was originally first excavated before the second world war. When we were finally able to, we were able to confirm it was a bridge built over an ancient canal, which we could confirm from alluvial deposits and the use of a drone."

The bridge, built out of mud-fired bricks, was also highly religiously significant as part of a processional route that led to the city's main plaza and temple.

"It was more than 40 metres long and eight to 10 metres wide and was one of the main access points to the ancient city of Girsu, which was one of the first cities in the world. It was the entry point for pilgrims during religious festivals -- including the city's tutelary god, Ningirsu -- and so was an important symbolic feature."

The Tello site, said Rey, has significant advantages for the programme launched two years ago to train Iraqi archaeologists.

Aside from its similarity to other major Iraqi sites, its location midway between Baghdad and Basra in a Shia majority area in the south of the country saw it insulated from much of the violence and destruction that followed the capture by Isis of large parts of northern Iraq.

Prominent among sites severely damaged by Isis was the ancient site of Nimrud, about 20 miles south of Mosul, which like Girsu was founded more than 3,300 years ago, where Isis not only destroyed the giant winged bulls that once stood sentry but left the site vulnerable to looters.

Destroying Great Mosque of al-Nuri 'is Isis declaring defeat' Read more "According to the official figures of the Iraqi state board of antiquities 70% of Nineveh, in Mosul province [once the centre of Isis's self-declared caliphate] was destroyed. In Nimrud we are talking about 80%, while there was also huge destruction too in Nebi Yunis," said Rey.

"A lot needs to be done to assess damage at those sites, which means that the fact that local architects can work in safety southern Iraq makes Tello an ideal site for training for what will be required at places like Nineveh and Nimrud."

Although the museum has already trained several all-male groups at Girsu, the next two groups will comprise only Iraqi women.

Among those who have been through the scheme is Mehdi Ali Raheem, a curator in the Iraq Museum, who spent nine weeks in London before continuing with field work at the site in Iraq.

"It is really important for the future. The conservation of the bridge and the preparation of site panels to explain our work to a wider audience will help bring tourists back to our country -- which was the cradle of civilisation -- first from the Middle East, and then international tourists," he said.